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Finding the Fourth Proportional to 2.39, 3.30 and 1.31

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Solution

The fourth proportional to 2.39, 3.30 and 1.31 is: 1.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.39 : 3.30 = 1.31 : x
  2. Step 2: Convert to fraction form
    2.39/3.30 = 1.31/x
  3. Step 3: Cross multiply
    2.39x = 3.30 × 1.31
  4. Step 4: Simplify right side
    2.39x = 4.33
  5. Step 5: Solve for x
    x = 4.33/2.39
  6. Step 6: Final answer
    x = 1.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.